Heating apparatus



Sept 28, w43. L. A. WILLIAMS, JR

HEATING APPARATUS l Filed Aug. 5, 1942 heated air is effective to heatPatented Sept. 28, 1943 HEATING ArrAnA'rUs Northfield, lll., assignor toLynn A. Williams,

AStewart-Warner Corporation,

Chicago, lll., a

corporation of Virginia Application August 3, 1942, Serial No. 453,347Claims. (Cl. 981) My invention relates generally to aircraft heatingapparatus, and more particularly to means for heating the gun turrets ofbombers.

Considerable difficulty has'been encountered in the heating of gunturrets of bombers in which a hemispherical transparent plastic. dome ismounted for rotation with the gun and gunners seat. This is duepartially to the fact that at high velocities considerable leakage ofcold air into the turret takes place because of the necessary clearancebetween the turret dome and the fuselage of the plane to permit rotationof the former. Furthermore, frosting of the dome, impairing the view ofthe gunner, presents a serious problem. Due to the high rate of heatdissipation from the surface ofthe dome, it is nearly impossible tosupply sufficient heat to the turret to maintain the entire space withinthe turret at a high temperature, particularly when the plane is flyingat high altitudes where the temperature may be in the order of 60 F.

To overcome these and other dilliculties, I have provided an improvedmeans for distributing heated air over the inner surface of.' thetransparent dome of a gunners turret whereby the the dome suinciently toprevent the formation of frost thereon.

It is thus an object of my invention to provide an improved apparatusfor heating gunners turrets on aircraft.

A further object is to provide an improved means for distributing heatsupplied to a gunner's turret in a manner to prevent the formation offrost on the transparent dome thereof and to prevent localized coolingof the dome by cold air leaking into the turret.

Other objects will appear description, reference being had to' theaccompanying drawing, in which:

Fig. 1 is an elevational view of a portion of an airplane showing thegunner's turret;

Fig. 2 is a vertical sectional view of the turret:

and

v Fig. 3 is a horizontal sectional view taken on the line 3-3 of Fig. 2.

As shown, the turret comprises a gunners compartment It, which may becylindrical in shape and the wall structure fuselage It. The gunnersseat and the gun mount are mounted for rotary movement about thevertical axis of the compartment I2. Rotating with the gun mount andgunners seat is the transparent plastic dome I6. This dome is providedwith an air exhaust tube i8, whichis freely swiveled at the apex of thedome so as to operate of which is xeci to theproject thin widearcuatefrom the following ner surface of the dome.

' dome and that the heated in the manner of a weather vane and provide asuillcient aspi ating effect to assure rapid ventilation of theI urrt.

Heated fair is su plied to the turret by a heater 20, which is suitablysecured to the compartment wall l2. This heater is preferably of theinternal combustion type, such, for example, as disclosed in priorPatent No. 2,191,178. The heater is provided 'with a suitable fan orblower causing flow of the heated Ventilating air through ari elbow 24into a. manifold 26. The manifold 26 provides a circular passageway 28between itand the upper edge portion of the `cylindrical wall i2.

of the passageway 28 2li to a diametrically The cross-sectionalareadecreases from. the elbow opposite point.

and an upwardlyextendof the manifold 26. fish-tail shape and theirplan-view, so that they streams of heated air at high velocity againstthe lower portion of the inner surface of the dome it. The heated Aairing flange 30 forming These nozzles are of z openings are arcuate intherefore tends to flow upwardly along the inner surface of the dome I6toward the discharge elbow I8. The -heat I is thus concentrated-on theplastic dome I6 and.

the temperature of the latter maintained sufficiently high to preventfrosting of its external surface or the condensation of moisture orfrosting on its inner surface.

The aggregate area vof the ends of the nozzles 32 is preferablyconsiderably less than the cross-sectional area of the elbow. 24, withthe result that substantially uniform distribution of heated air nowamong the several nozzles is obtained. The fact that the nozzle portsform. restrictions also'results in an increase in the velocity at whichthe heated air is projected against the inner surface of the dome, withthe advantage that there is a more emcient exchange of heat from theeffect, tending to prevent the formation ofyand to remove, 4any frost orcondensation .onthe in- If desired, the nozzles 32 may be separate fromthe wall 12' and be welded or otherwise secured thereto. However, theconstruction i shown, in which-theupper'edge of the wall l2 is formed toprovide the nozzles 32, constitutes a relatively simple and effectivedistribution 'of the heated air along the entire supplied by the heater2B,

the discharge ports at v heated air to the v air has a mild scouring'means for securing uniform lower edge of the inner surface of the dome[I6 and causing the heated air to flow upwardly in relatively thinlayers along the inner surface of the dome.

Since the sheet-like jets of heated air discharged by the nozzles 32 cutacross any air currents resultant from leakage around the base of thedome i6, such leakage currents will not produce localized cold areas onthe dome I6, since any such incipient streams of cold air are broken upand heated by the air ejected from the nozzles 32.

While I have shown. and described a particular embodiment of Amyinvention', it will be apparent to those skilled in the art thatnumerous variations and modifications may be made therein withoutdeparting from the underlying principles of the invention. I thereforedesire, by the following claims, to include within the scope of myinvention all such variations and modifications by which substantiallythe results of my invention may be obtained by the use of substantiallythe same or equivalent means.

I claim:

l. In an aircraft turret having a movable transparent dome and having afixed turret compartment wall, the combination of means for supplying astream of heated air, a manifold connected to receive heat from saidmeans and extending around the upper edge of the turret compartment,said manifold having a portion deiining with the upper edge of theturret compartment wall a, port for the discharge of a relatively thinsheet of heated air along the lower inner edge surface of the dome.

2. In an aircraft gun turret having a movable transparent dome providedwith an air exhaust port at its top, a relatively fixed turretcompartment wall, a heater supported by said wal1 and having means fordischarging a stream of heated air, means forming a manifold receivingheated air from said heater andv extending around the top of saidcompartment wall, and a plurality of' nozzles communicating with saidmanifold and directing the ow of heated air therefrom tothe inner loweredge surface of said dome.

3. In an aircraft gun turret having. a generally hemispherical dome, aheater having an outlet for the discharge of heated air therefrom,conduit means connected to said outlet and conformed to discharge theheated air near the-base of said dome against the inner surface thereof,and means for withdrawing air from the top of said dome.

4. An aircraft gun turret having a transparent dome provided with acentral air exhaust opening at its top, a heater having means forsupplying heated air under pressure, and means receiving heated air fromsaid heater 'and discharging it in a sheet-like stream along the bottomof said dome and against the inner surface thereof.

5. In an aircraft gun turret having a wall fixed with respect to theaircraft and having a dome mounted for movement with respect to theaircraft, a heater of the internal combustion type fixed to theaircraft, a manifold receiving heated air from said heater and securedto said wail, and'a plurality of ,heated air outlet nozzles connected tosaid manifold and directed to project the heated air in thin streamsagainst the inner surface of said dome near the base thereof.

n LYNN A. WILLIAMS. JR.

